class Student:
    name = None
    age = None
    __phone = None

    def set_phone(self, phone):
        self.__phone = phone

    def get__phone(self):
        print(f"当前的手机号为：{self.__phone}")
        self.__good()

    def __good(self):
        print("执行一次good方法")


stu1 = Student()
stu1.name = '张三'
# 执行报错
# stu1.__phone = '185464654'
stu1.set_phone('185464654')
print(f"电话为：{stu1.get__phone()}")

# 执行报错
# stu1.__good()